Associate Professor of Public Health Nutrition
Director of Public Health Nutrition
Director of Doctoral Studies
- Professional overview
Niyati Parekh, Associate Professor of Public Health Nutrition, worked as a practicing clinical nutritionist in India prior to working in academia and public health. She was involved in several projects related to community outreach within local neighborhoods, such as establishing a breast milk bank in a Mumbai hospital and serving mothers from urban slums. Most notably, she worked as an oncology dietitian, working at the bedside of cancer patients, some living without an esophagus or stomach. While serving cancer patients, the importance of nutrition in cancer care became apparent to her. She decided to pursue a career at the intersection of biology, clinical nutrition and population science, and came to the United States for her training. She subsequently completed her doctoral degree in nutritional epidemiology.
During her eight year tenure at NYU, she has primarily focused on nutrition and chronic diseases. Particularly, she has investigated the links between diet, physical activity, obesity and cancer. Currently, she is Principal Investigator of The Cancer, Insulin Resistance, and Lifestyle (CIRCLE) Study in the multi-generational Framingham Heart Study cohort, funded by the American Cancer Society. This study exams obesity and glucose dysregulation as risk factors for developing cancer in US population.
Based on the findings from the CIRCLE study, Niyati and Dr. Paul Krebs, Co-Principal Investigator of HEAL and a faculty member at NYU School of Medicine, pursued funding a pilot study, The Healthy Eating and Living against Breast Cancer (HEAL-Breast Cancer) to provide breast cancer survivors with nutrition literacy programming. The program concludes with an Iron Chef competition in which the women get into the kitchen, and put into practice everything that they've learned. "It's not just about nutrition, it's about how to make those changes in your day to day life," said Niyati. Her community outreach extends to nutrition workshops and projects in her children's schools.
Niyati has been interested in understanding early-life risk factors of chronic diseases. Recently, Niyati served as a Visiting Scholar at Karolinska Institutet and the Linköping University, funded by County Council of Östergötland, Sweden. She collaborated with faculty and doctoral students on analyses addressing body composition and eating patterns in preschool children, who were enrolled in an mHealth intervention. This work has informed her current grant proposal in which she is preparing to study infancy and childhood-related risk factors of adult cancers.
On campus, Niyati has taught Global Nutrition, Public Health Nutrition, as well as methodology courses for which she has won teaching awards. Niyati thrives on putting nutrition into a global context for her students through study abroad experiences. Notably, she taught a course on Public Health Nutrition and Chronic Disease in Mexico. She fuels conversation around the nutrition and risk factors for chronic diseases (diabetes, heart disease) through visits to the marketplaces and local cantinas. She will be involved in teaching study abroad courses at CGPH.
Niyati's highlights at NYU have been the mentorship of doctoral students. Her first student won the "Best Dissertation Award" from 70 eligible candidates at Steinhardt, who then moved on to be employed at the Harvard School of Public Health. She occasionally enjoys cooking for her doctoral students during her downtime. "They can taste the goodness of nutrition in my food. I don't always have to teach it," she said with a warm laugh.
Dr. Parekh received her MS in Foods, Nutrition, and Clinical Dietetics in 1997 and is a credentialed Registered Dietitian from India. In 2005, she earned a PhD in Nutritional Sciences and Population Health from the University of Wisconsin-Madison. Thereafter, she was awarded a 2-year Department of Defense postdoctoral fellowship at the Rutgers-Cancer Institute of New Jersey.
BS, Life Sciences and Biotechnology, Mumbai University, IndiaMS, Foods, Nutrition, and Clinical Dietetics, Mumbai University, IndiaPhD, Nutritional Sciences (minor Population Health Sciences), University of Wisconsin-Madison, Madison, WI
- Areas of research and study
CancerChronic DiseasesEpidemiologyNutritionObesityPopulation HealthPublic Health Nutrition
Birth weight, early life weight gain and age at menarche: a systematic review of longitudinal studiesJuul, F., Chang, V.W., Brar, P., & Parekh, N.
Journal titleObesity Reviews
Background and objective: Adiposity in pre- and postnatal life may influence menarcheal age. Existing evidence is primarily cross-sectional, failing to address temporality, for which the role of adiposity in early life remains unclear. The current study sought to systematically review longitudinal studies evaluating the associations between birth weight and infant/childhood weight status/weight gain in relation to menarcheal age. Methods: PubMed, EMBASE, Web of Science, Global Health (Ovid) and CINAHL were systematically searched. Selected studies were limited to English-language articles presenting multi-variable analyses. Seventeen studies reporting risk estimates for birth weight (n = 3), infant/childhood weight gain/weight status (n = 4) or both (n = 10), in relation to menarcheal age were included. Results: Lower vs. higher birth weight was associated with earlier menarche in nine studies and later menarche in one study, while three studies reported a null association. Greater BMI or weight gain over time and greater childhood weight were significantly associated with earlier menarche in nine of nine and six of seven studies, respectively. Conclusions: Studies suggested that lower birth weight and higher body weight and weight gain in infancy and childhood may increase the risk of early menarche. The pre- and postnatal period may thus be an opportune time for weight control interventions to prevent early menarche, and its subsequent consequences.
Carbohydrate nutrition and risk of adiposity-related cancers: results from the Framingham Offspring cohort (1991–2013)Makarem, N., Bandera, E.V., Lin, Y., Jacques, P.F., Hayes, R.B., & Parekh, N.
Journal titleBritish Journal of Nutrition
Higher carbohydrate intake, glycaemic index (GI), and glycaemic load (GL) are hypothesised to increase cancer risk through metabolic dysregulation of the glucose-insulin axis and adiposity-related mechanisms, but epidemiological evidence is inconsistent. This prospective cohort study investigates carbohydrate quantity and quality in relation to risk of adiposity-related cancers, which represent the most commonly diagnosed preventable cancers in the USA. In exploratory analyses, associations with three site-specific cancers: breast, prostate and colorectal cancers were also examined. The study sample consisted of 3184 adults from the Framingham Offspring cohort. Dietary data were collected in 1991–1995 using a FFQ along with lifestyle and medical information. From 1991 to 2013, 565 incident adiposity-related cancers, including 124 breast, 157 prostate and sixty-eight colorectal cancers, were identified. Cox proportional hazards models were used to evaluate the role of carbohydrate nutrition in cancer risk. GI and GL were not associated with risk of adiposity-related cancers or any of the site-specific cancers. Total carbohydrate intake was not associated with risk of adiposity-related cancers combined or prostate and colorectal cancers. However, carbohydrate consumption in the highest v. lowest quintile was associated with 41 % lower breast cancer risk (hazard ratio (HR) 0·59; 95 % CI 0·36, 0·97). High-, medium- and low-GI foods were not associated with risk of adiposity-related cancers or prostate and colorectal cancers. In exploratory analyses, low-GI foods, were associated with 49 % lower breast cancer risk (HR 0·51; 95 % CI 0·32, 0·83). In this cohort of Caucasian American adults, associations between carbohydrate nutrition and cancer varied by cancer site. Healthier low-GI carbohydrate foods may prevent adiposity-related cancers among women, but these findings require confirmation in a larger sample.
Nutrition Literacy among Cancer Survivors: Feasibility Results from the Healthy Eating and Living Against Breast Cancer (HEAL-BCa) Study: a Pilot Randomized Controlled TrialParekh, N., Jiang, J., Buchan, M., Meyers, M., Gibbs, H., & Krebs, P.
Journal titleJournal of Cancer Education
Knowledge of nutrition among breast cancer patients is insufficient, despite their motivation to seek valid information about healthy food choices. This study examines the feasibility of nutrition education workshops for cancer survivors, to inform the design of a multi-center intervention. Fifty-nine female English-speaking breast cancer patients, who had completed treatment, were enrolled. Participants were randomized to the intervention or control group. The intervention group attended six nutrition education sessions, and the control group received brochures. Measurements were done at baseline and 3-month follow-up and included the Assessment Instrument for Breast Cancer (NLit-BCa), fruit/vegetable and general health literacy screeners. Height and weight were measured. Changes in nutrition literacy, health literacy, and food intake from baseline to follow-up (within-group change) were calculated for both groups (effect sizes were reported as Cohen’s d). Participants were mostly white, with a mean age of 58 years, BMI of 31.6 kg/m2, and had college degrees. Follow-up rates were high (89% = control and 77% = intervention group). At baseline, participants scored high for most NLit-BCa assessment components except food portions in both groups. At the 3-month follow-up, effect sizes (d) on the NLit-BCa ranged from −0.5 to 0.16. The study met its recruitment goals within 6 months. Focus groups indicated that (a) attending six sessions was acceptable, (b) patients found social/emotional support, (c) improvements should include information for special diets and booster sessions. This pilot study suggests that the intervention was acceptable and that scaling up of this intervention is feasible and could provide benefit to breast cancer survivors.
Consumption of whole grains and cereal fiber in relation to cancer risk: A systematic review of longitudinal studiesMakarem, N., Nicholson, J.M., Bandera, E.V., McKeown, N.M., & Parekh, N.
Journal titleNutrition Reviews
Context: Evidence from previous reviews is supportive of the hypothesis that whole grains may protect against various cancers. However, the reviews did not report risk estimates for both whole grains and cereal fiber and only case-control studies were evaluated. It is unclear whether longitudinal studies support this conclusion. Objective: To evaluate associations between whole grains and cereal fiber in relation to risk of lifestyle-related cancers data from longitudinal studies was evaluated. Data Sources: The following 3 databases were systematically searched: PubMed, EMBASE, and Cochrane CENTRAL. Study Selection: A total of 43 longitudinal studies conducted in Europe and North America that reported multivariable-adjusted risk estimates for whole grains (n=14), cereal fiber (n=23), or both (n=6) in relation to lifestyle-related cancers were included. Data Extraction: Information on study location, cohort name, follow-up duration, sample characteristics, dietary assessment method, risk estimates, and confounders was extracted. Data Synthesis: Of 20 studies examining whole grains and cancer, 6 studies reported a statistically significant 6%-47% reduction in risk, but 14 studies showed no association. Of 29 studies examining cereal fiber intake in relation to cancer, 8 showed a statistically significant 6%-49% reduction in risk, whereas 21 studies reported no association. Conclusions: This systematic review concludes that most studies were suggestive of a null association. Whole grains and cereal fiber may protect against gastrointestinal cancers, but these findings require confirmation in additional studies.
Explaining racial/ethnic dietary patter ns in relation to type 2 diabetes: An analysis of NHAN ES 2007-2012Nowlin, S.Y., Cleland, C.M., Vadiveloo, M., Parekh, N., D'Eramo Melkus, G., & Hagan, H.
Journal titleEthnicity and Disease
Objective: The purpose of this article is to examine sociodemographic and health behavior factors associated with dietary intake as measured by the healthy eating index (HEI-2010) for persons with and without diabetes (T2D). Design: A secondary data analysis of three NHANES data cycles spanning 2007-2012. Multiple linear regression assessed racial/ ethnic differences in HEI-2010 scores in those without T2D, with T2D, and with undiagnosed T2D. Participants: The sample included nonpregnant adults aged ≥20 years who had two days of reliable dietary recall data. Outcome Measures: Total scores for the HEI-2010. Results: For those without T2D, there was a significant association between race/ ethnicity and HEI score, with non-Hispanic Blacks achieving significantly lower scores than their non-Hispanic White counterparts. Differences in HEI-2010 score were also associated with age, sex, smoking status and time spent in the United States. Racial/ ethnic differences in dietary patterns were present, but not significant in those with undiagnosed or diagnosed T2D. Conclusions: Racial/ethnic disparities in dietary patterns are present in individuals without T2D, but differences are not statistically significant in those with undiagnosed or diagnosed T2D. Non-Hispanic Blacks without T2D received significantly lower HEI-2010 scores than non-Hispanic Whites. Further research is necessary to determine whether or not similarities in dietary intake across racial/ethnic groups with T2D will be reflected in diabetes-related health outcomes in this population.
Increasing mortality in the United States from cholangiocarcinoma: An analysis of the National Center for Health Statistics DatabaseYao, K.J., Jabbour, S., Parekh, N., Lin, Y., & Moss, R.A.
Journal titleBMC Gastroenterology
Background: While mortality in the United States has decreased for most cancers, mortality from combined hepatocellular liver cancer and intrahepatic cholangiocarcinoma (ICC) has increased and ranked 1st in annual percent increase among cancer sites. Because reported statistics combine ICC with other liver cancers, mortality rates of cholangiocarcinoma (CCA) remain unknown. This study is to determine CCA mortality trends and variation based on national data. Methods: This nation-wide study was based on the underlying cause of death data collected by the National Center for Health Statistics (NCHS) between 1999 and 2014. The Center for Disease Control (CDC) Wide-ranging Online Data for Epidemiologic Research (WONDER) system was used to obtain data. ICC and extra-hepatic CCA (ECC) were defined by ICD-10 diagnosis codes. Age-adjusted mortality rate was standardized to the US population in 2000. Results: There were more than 7000 CCA deaths each year in the US after 2013. CCA mortality for those aged 25+ increased 36 % between 1999 and 2014, from 2.2 per 100,000 (95 % confidence interval [CI] 2.1-2.3) to 3.0 per 100,000 (95 % CI, 2.9-3.1). Mortality rates were lower among females compared with males (risk ratio [RR] 0.78, 95 % CI 0.77-0.79). Asians had the highest mortality. Between 2004 and 2014, the increase in CCA mortality was highest among African Americans (45 %) followed by Asians (22 %), and whites (20 %). Conclusion: Based on the most recent national data, CCA mortality rates have increased substantially in the past decade. Among different race/ethnic groups, African Americans have the highest increase in CCA mortality.
Concordance with DASH diet and blood pressure change: Results fromthe Framingham Offspring Study (1991-2008)Jiang, J., Liu, M., Troy, L.M., Bangalore, S., Hayes, R.B., & Parekh, N.
Journal titleJournal of Hypertension
Background: Concordance with the Dietary Approaches to Stop Hypertension (DASH) diet has been shown to reduce blood pressure (BP) in short-term intervention studies, but the long-term impact is unclear. We evaluated the association of DASH diet concordance with BP trajectories and incidence of hypertension, in 2187 men and women (mean age 52.5 years at baseline) participating in the Framingham Offspring cohort. Method: Diet and BP were assessed from 1991 to 2008, with a median follow-up time of 13.4 years. DASH scores (ranging from 0 for worst to 10 for best concordance with DASH diet) were calculated by summing 10 food components that comprise the DASH diet pattern, including fruits and vegetables, low-fat dairy products, lean meat, and plant-based protein. Mixed-effect and Cox regression models were applied, to assess the association of DASH diet concordance with BP longitudinal change and with incidence of hypertension, respectively. All analyses were adjusted for age, sex, smoking status, history of diabetes, BMI, and physical activity. Result: Overall, SBP increased by 0.34mmHg and DBP by 0.10mmHg annually, in the Framingham Offspring cohort. Every unit increase in the DASH score resulted in a modest increase in SBP of 0.054 mmHg/year (P=0.028). No associations were observed between DASH diet concordance and DBP or incidence of hypertension. Conclusion: Long-term concordance with the DASH diet was not associated with a decreasing BP trajectory over time, or with decreased incidence of hypertension, in this population of middle-aged adults.
Concordance with World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) guidelines for cancer prevention and obesity-related cancer risk in the Framingham Offspring cohort (1991–2008)Makarem, N., Lin, Y., Bandera, E.V., Jacques, P.F., & Parekh, N.
Journal titleCancer Causes and Control
Purpose: This prospective cohort study evaluates associations between healthful behaviors consistent with WCRF/AICR cancer prevention guidelines and obesity-related cancer risk, as a third of cancers are estimated to be preventable. Methods: The study sample consisted of adults from the Framingham Offspring cohort (n = 2,983). From 1991 to 2008, 480 incident doctor-diagnosed obesity-related cancers were identified. Data on diet, measured by a food frequency questionnaire, anthropometric measures, and self-reported physical activity, collected in 1991 was used to construct a 7-component score based on recommendations for body fatness, physical activity, foods that promote weight gain, plant foods, animal foods, alcohol, and food preservation, processing, and preparation. Multivariable Cox regression models were used to estimate associations between the computed score, its components, and subcomponents in relation to obesity-related cancer risk. Results: The overall score was not associated with obesity-related cancer risk after adjusting for age, sex, smoking, energy, and preexisting conditions (HR 0.94, 95 % CI 0.86–1.02). When score components were evaluated separately, for every unit increment in the alcohol score, there was 29 % lower risk of obesity-related cancers (HR 0.71, 95 % CI 0.51–0.99) and 49–71 % reduced risk of breast, prostate, and colorectal cancers. Every unit increment in the subcomponent score for non-starchy plant foods (fruits, vegetables, and legumes) among participants who consume starchy vegetables was associated with 66 % reduced risk of colorectal cancer (HR 0.44, 95 % CI 0.22–0.88). Conclusions: Lower alcohol consumption and a plant-based diet consistent with the cancer prevention guidelines were associated with reduced risk of obesity-related cancers in this population.
Dietary variety is inversely associated with body adiposity among us adults using a novel food diversity indexVadiveloo, M., Beth Dixon, L., Mijanovich, T., Elbel, B.D., & Parekh, N.
Journal titleJournal of Nutrition
Background: Consuming a variety (vs. monotony) of energy-poor, nutrient-dense foods may help individuals adhere to dietary patterns favorably associated with weight control. Objective: The objective of this study was to examine whether greater healthful food variety quantified using the US Healthy Food Diversity (HFD) index favorably influenced body adiposity. Methods: Men and nonpregnant, nonlactating women aged ≥20 y with two 24-h recalls from the cross-sectional NHANES 2003-2006 (n = 7470) were included in this study. Dietary recalls were merged with the MyPyramid Equivalent database to generate the US HFD index, which ranges from 0 to ~1, with higher scores indicative of diets with a higher number and proportion of healthful foods. Multiple indicators of adiposity including BMI, waist-to-height ratio, android-to-gynoid fat ratio, fat mass index (FMI), and percentage body fat were assessed across US HFD index quintiles. ORs and 95% CIs were computed with use of multivariable logistic regression (SAS v. 9.3). Results: The US HFD index was inversely associated with most adiposity indicators in both sexes. After multivariable adjustment, the odds of obesity, android-to-gynoid ratio >1, and high FMI were 31-55% lower (P-trend < 0.01) among women in quintile 5 vs. quintile 1 of the US HFD index. Among men, the odds of obesity, waist-to-height ratio =0.5, and android-to-gynoid ratio >1 were 40-48% lower (P-trend = 0.01) in quintile 5 vs. quintile 1 of the US HFD index. Conclusions: Higher US HFD index values were inversely associated with indicators of body adiposity in both sexes, indicating that greater healthful food variety may protect against excess adiposity. This study explicitly recognizes the potential benefits of dietary variety in obesity management and provides the foundation to support its ongoing evaluation.
Dietary Variety: An Overlooked Strategy for Obesity and Chronic Disease ControlVadiveloo, M.K., & Parekh, N.
Journal titleAmerican Journal of Preventive Medicine
Greater healthful food variety as measured by the US healthy food diversity index is associated with lower odds of metabolic syndrome and its components in US adults.Vadiveloo, M., Parekh, N., & Mattei, J.
Journal titleJournal of Nutrition
Insulin receptor variants and obesity-related cancers in the Framingham Heart StudyParekh, N., Guffanti, G., Lin, Y., Ochs-Balcom, H.M., Makarem, N., & Hayes, R.
Journal titleCancer Causes and Control
Purpose: The insulin-signaling pathway plays a pivotal role in cancer biology; however, evidence of genetic alterations in human studies is limited. This case–control study nested within the Framingham Heart Study (FHS) examined the association between inherited genetic variation in the insulin receptor (INSR) gene and obesity-related cancer risk. Methods: The study sample consisted of 1,475 controls and 396 cases from the second familial generation of the FHS. Participants who provided consent were genotyped. Nineteen single-nucleotide polymorphisms (SNPs) in the INSR gene were investigated in relation to risk of obesity-related cancers combined and breast, prostate and colorectal cancers. Generalized estimation equation models controlling for familial correlations and include age, sex, smoking and body mass index as covariates, assuming additive models, were used. Results: Three SNPs, rs2059807, s8109559 and rs919275, were significantly associated with obesity-related cancers (p value < 0.02) with the most significantly associated SNP being rs2059807 (p value = 0.008). Carriers of two copies of SNP rs2059807 risk allele T were significantly less prevalent among subjects with obesity-related cancers [f(TT)cases = 14 vs. f(TT)controls = 18 %; OR 1.23]. In exploratory analyses evaluating site-specific cancers, the INSR rs2059807 association with these cancers was consistent with that observed for the main outcome (ORs colorectal cancer = 1.5, breast cancer = 1.29, prostate = 1.06). There was no statistically significant interaction between the INSR–SNP and blood glucose in relation to obesity-related cancer. Conclusions: The INSR gene is implicated in obesity-related cancer risk, as 3 of 19 SNPs were nominally associated, after false discovery rate (FDR) correction, with the main outcome. Risk allele homozygotes (rs2059807) were less prevalent among subjects with obesity-related cancer. These results should be replicated in other populations to confirm the findings.
Sensitivity and specificity of malnutrition screening tools used in the adult hospitalized patient setting a systematic reviewPlatek, M.E., Hertroijs, D.F.L., Nicholson, J.M., & Parekh, N.
Journal titleTopics in Clinical Nutrition
Adult hospitalized patients are at risk for malnutrition. The sensitivity and specificity of screening tools were compared with Subjective Global Assessment. Methods included a systematic review using PubMed, CINAHL Plus, and EMBASE through April 2014. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies method. The results showed that the Malnutrition Universal Screening Tool, Nutrition Risk Screening-2002, and Malnutrition Screening Tool were most frequently tested. The specificity was generally good (>80%), but sensitivity was variable. Malnutrition Universal Screening Tool, Nutrition Risk Screening-2002, and Malnutrition Screening Tool are screening tools that consider population characteristics and risk cut points and are easy to administer. Key words: malnutrition, nutrition assessment, nutrition screening, sensitivity and specificity, subjective global assessment, undernutrition.
Development and evaluation of the US Healthy Food Diversity indexVadiveloo, M., Dixon, L.B., Mijanovich, T., Elbel, B.D., & Parekh, N.
Journal titleThe British journal of nutrition
Varied diets are diverse with respect to diet quality, and existing dietary variety indices do not capture this heterogeneity. We developed and evaluated the multidimensional US Healthy Food Diversity (HFD) index, which measures dietary variety, dietary quality and proportionality according to the 2010 Dietary Guidelines for Americans (DGA). In the present study, two 24 h dietary recalls from the 2003-6 National Health and Nutrition Examination Survey (NHANES) were used to estimate the intake of twenty-six food groups and health weights for each food group were informed by the 2010 DGA. The US HFD index can range between 0 (poor) and 1 - 1/n, where n is the number of foods; the score is maximised by consuming a variety of foods in proportions recommended by the 2010 DGA. Energy-adjusted Pearson's correlations were computed between the US HFD index and each food group and the probability of adequacy for fifteen nutrients. Linear regression was run to test whether the index differentiated between subpopulations with differences in dietary quality commonly reported in the literature. The observed mean index score was 0·36, indicating that participants did not consume a variety of healthful foods. The index positively correlated with nutrient-dense foods including whole grains, fruits, orange vegetables and low-fat dairy (r 0·12 to 0·64) and negatively correlated with added sugars and lean meats (r - 0·14 to - 0·23). The index also positively correlated with the mean probability of nutrient adequacy (r 0·41; P< 0·0001) and identified non-smokers, women and older adults as subpopulations with better dietary qualities. The US HFD index may be used to inform national dietary guidance and investigate whether healthful dietary variety promotes weight control.
Racial differences in the association of insulin-like growth factor pathway and colorectal adenoma riskOchs-Balcom, H.M., Vaughn, C.B., Nie, J., Chen, Z., Thompson, C.L., Parekh, N., … Li, L.
Journal titleCancer Causes and Control
Purpose: Insulin resistance is believed to play an important role in the link between energy imbalance and colon carcinogenesis. Emerging evidence suggests that there are substantial racial differences in genetic and anthropometric influences on insulin-like growth factors (IGFs); however, few studies have examined racial differences in the associations of IGFs and colorectal adenoma, precursor lesions of colon cancer. Methods: We examined the association of circulating levels of IGF-1, IGFBP-3 and IGFBP-1, and SNPs in the IGF-1 receptor (IGF1R), IGF-2 receptor (IGF2R), and insulin receptor genes with risk of adenomas in a sample of 410 incident adenoma cases and 1,070 controls from the Case Transdisciplinary Research on Energetics and Cancer (TREC) Colon Adenomas Study. Results: Caucasians have higher IGF-1 levels compared to African Americans; mean IGF-1 levels are 119.0 ng/ml (SD = 40.7) and 109.8 ng/ml (SD = 40.8), respectively, among cases (p = 0.02). Mean IGF-1 levels are also higher in Caucasian controls (122.9 ng/ml, SD = 41.2) versus African American controls (106.9, SD = 41.2), p = 0.001. We observed similar differences in IGFBP3 levels by race. Logistic regression models revealed a statistically significant association of IGF-1 with colorectal adenoma in African Americans only, with adjusted odds ratios (ORs) of 1.68 (95 % CI 1.06-2.68) and 1.68 (95 % CI 1.05-2.71), respectively, for the second and third tertiles as compared to the first tertile. One SNP (rs496601) in IGF1R was associated with adenomas in Caucasians only; the per allele adjusted OR is 0.73 (95 % CI 0.57-0.93). Similarly, one IGF2R SNP (rs3777404) was statistically significant in Caucasians; adjusted per allele OR is 1.53 (95 % CI 1.10-2.14). Conclusion: Our results suggest racial differences in the associations of IGF pathway biomarkers and inherited genetic variance in the IGF pathway with risk of adenomas that warrant further study.
Treatment and outcomes in diabetic breast cancer patientsGold, H.T., Makarem, N., Nicholson, J.M., & Parekh, N.
Journal titleBreast Cancer Research and Treatment
Effective breast cancer management is more complex with diabetes present and may contribute to poor outcomes. Therefore, we conducted two simultaneous systematic reviews to address the association of diabetes with (1) treatment patterns in breast cancer patients and (2) breast cancer recurrence rates or breast cancer-specific and all-cause mortality. We searched major databases for English language peer-reviewed studies through November 2013, which addressed either of the above research questions, following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) method. Analyses compared treatment patterns or health outcomes for breast cancer subjects with and without diabetes. We used STROBE quality criteria and conducted a random-effects meta-analysis of all-cause mortality. The review yielded 11 publications for question 1 and 26 for question 2, with nine overlapping. Treatment studies showed chemotherapy was less likely in patients with diabetes. Of 22 studies, 21 assessing all-cause mortality indicated a statistically significant increased overall mortality for patients with diabetes (hazard ratios: 0.33-5.40), with meta-analysis of eligible studies indicating a 52 % increased risk. Nine studies assessing breast cancer-specific mortality had inconsistent results, with five showing significantly increased risk for diabetes patients. Results were inconsistent for recurrence and metastases. The majority of studies reported detrimental associations between diabetes and optimal treatment or all-cause mortality among women with breast cancer. Divergence in variable and outcomes inclusion and definitions, potential participation bias in individual studies, and differing analytic methods make inferences difficult. This review illuminates the importance of the impact of diabetes on breast cancer patients and explicitly recognizes that co-management of conditions is necessary to prevent excess morbidity and mortality.
Trends in dietary carbohydrate consumption from 1991 to 2008 in the Framingham Heart Study Offspring CohortMakarem, N., Scott, M., Quatromoni, P., Jacques, P., & Parekh, N.
Journal titleThe British journal of nutrition
The intake of carbohydrates has been evaluated cross-sectionally, but not longitudinally in an ageing American adult population. The aim of the present study was to examine trends in the intake of dietary carbohydrates and their major food sources among the Framingham Heart Study Offspring (FOS) cohort, which had been uniquely tracked for 17 years in the study. The FOS cohort was recruited in 1971-1975. Follow-up examinations were conducted, on average, every 4 years. Dietary data collection began in 1991 (examination 5) using a validated semi-quantitative FFQ. The study included 2894 adults aged ≥ 25 years with complete dietary data in at least three examinations from 1991 to 2008. Descriptive statistics were generated using SAS version 9.3, and a repeated-measures model was used to examine trends in the intake of carbohydrates and their food sources in the whole sample, and by sex and BMI category. Over 17 years of follow-up, the percentage of energy from total carbohydrates (51·0-46·8 %; P for trend < 0·001) and total sugars (18·2-16·6 %; P for trend < 0·001) decreased. There was a decrease in the percentage of energy from fructose (5·4-4·7 %; P for trend < 0·001) and sucrose (9·8-8·8 %; P for trend < 0·001). Dietary fibre intake increased (18·0-19·2 g/d; P for trend < 0·001). The number of weekly servings of yeast bread, soft drinks/soda, cakes/cookies/quick breads/doughnuts, potatoes, milk, pasta, rice and cooked grains, fruit juice/drinks, potato chips/maize chips/popcorn, and lunch foods (e.g. pizzas and burgers) decreased significantly (P for trend < 0·001), while the intake of ready-to-eat cereals, legumes, fruits, dairy products, candy and ice cream/sherbet/frozen yogurt increased significantly (P for trend<0·04) . Similar trends were observed when the analyses were stratified by sex and BMI. The present results suggest favourable trends in dietary carbohydrate consumption, but dietary guidelines for fruits, vegetables and fibre were not met in this cohort.
Trends in dietary fat and high-fat food intakes from 1991 to 2008 in the framingham heart study participantsVadiveloo, M., Scott, M., Quatromoni, P., Jacques, P., & Parekh, N.
Journal titleThe British journal of nutrition
Few longitudinal studies carried out in US adults have evaluated long-term dietary fat intakes and compared them with the national recommendations during the two-decade period when the prevalence of obesity and insulin resistance increased substantively. In the present study, we examined trends in the intakes of dietary fats and rich dietary sources of fats in the Framingham Heart Study Offspring Cohort over a 17-year period. The cohort was established in 1971-75 with follow-up examinations being conducted approximately every 4 years. Dietary data were collected using a semi-quantitative FFQ beginning in 1991 (exam 5). We included 2732 adults aged ≥A 25 years with complete dietary data in at least three examinations from 1991 to 2008. Descriptive statistics were generated using SAS version 9.3, and a repeated-measures model was used to examine trends in macronutrient and food intakes using R. Over the 17 years of follow-up, the percentage of energy derived from total fat and protein increased (27·3-29·8A % of energy and 16·8-18·0A % of energy, respectively) and that derived from carbohydrate decreased (51·0- 46·8A % of energy; P-trend
Associations between dietary variety and measures of body adiposity: a systematic review of epidemiological studies.Vadiveloo, M., Dixon, L.B., & Parekh, N.
Journal titleThe British journal of nutrition
Dietary variety is positively correlated with energy intake in most studies. However, the associations between dietary variety and measures of body adiposity are inconsistent in the literature, which limits the development of clear national nutrition recommendations regarding dietary variety. In the present systematic review, we critically evaluate the associations between dietary variety and measures of body adiposity among healthy adults within the existing literature. We conducted a systematic search of the MEDLINE and Web of Science databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement to examine these associations. We identified twenty-six studies in total that investigated the associations between dietary variety and body adiposity measures. Total variety was non-significantly associated with body adiposity in most studies, while variety in recommended foods was either inversely associated (six out of ten studies) or non-significantly associated (three out of ten studies) with body adiposity. Conversely, variety in non-recommended foods (i.e. sources of added sugars and solid fats) increased the likelihood of excess adiposity in most studies (six out of nine studies). Definitions and measurement of dietary variety were inconsistent across studies and contributed to some of the discrepancies noted in the literature. In conclusion, among the studies that met the inclusion criteria for the present review, dietary variety was inconsistently associated with body adiposity in diverse populations. Using consistent and specific definitions of dietary variety may help provide further insight into the associations between dietary variety and excess adiposity before definitive public health messages are ma
Consumption of sugary foods and drinks and risk of endometrial cancerKing, M.G., Chandran, U., Olson, S.H., Demissie, K., Lu, S.E., Parekh, N., & Bandera, E.V.
Journal titleCancer Causes and Control
Consumption of foods high in sugar promotes insulin production, which has been linked to endometrial carcinogenesis. We evaluated the impact of dietary intake of sugary foods and beverages, as well as added sugar and total sugar on endometrial cancer risk in a population-based case-control study, including 424 cases and 398 controls. Participants completed an interview and food frequency questionnaire, and provided self-recorded waist and hip measurements. Women in the highest quartile of added sugar intake had significantly increased endometrial cancer risk (OR = 1.84, 95 % CI 1.16-2.92). Among women with waist-to-hip ratio ≥0.85, risk was significantly higher for the highest versus lowest tertile of added sugar intakes (OR = 2.50, 95 % CI 1.38-4.52). The association with added sugar also became stronger when analyses were restricted to never users of hormone replacement therapy (OR = 2.03; 95 % CI 1.27-3.26, for highest versus lowest tertile). There was little evidence of effect modification by body mass index or physical activity. Given the high prevalence of intake of sugary foods and drinks in Western populations, additional research is warranted to confirm our findings on endometrial cancer.
Diabetes mellitus as a risk factor for gastrointestinal cancers among postmenopausal womenLuo, J., Chlebowski, R., Liu, S., McGlynn, K.A., Parekh, N., White, D.L., & Margolis, K.L.
Journal titleCancer Causes and Control
Objectives: While diabetes has been linked to several cancers in the gastrointestinal (GI) tract, findings have been mixed for sites other than colorectal and liver cancer. We used the Women's Health Initiative (WHI) data and conducted a comprehensive assessment of associations between diabetes and GI malignancy (esophagus, stomach, liver, biliary, pancreas, colon, and rectal). Methods: A total of 145,765 postmenopausal women aged 50-79 enrolled in the WHI were followed for a mean 10.3 years. Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for the association between GI cancers and diagnosed diabetes, including its duration and treatment. Results: Diabetes at enrollment was associated with increased risk of liver (HR = 2.97; 95 % CI, 1.66-5.32), pancreatic (HR = 1.62; 95 % CI, 1.15-2.30), colon (HR = 1.38; 95 % CI, 1.14-1.66), and rectal (HR = 1.87, 95 % CI: 1.22-2.85) cancer. Diabetes severity, assessed by duration or need for pharmacotherapy, appeared to have stronger links to risk of liver, pancreatic, and rectal cancer, but not colon cancer. There was no statistically significant association of diabetes with biliary, esophageal, and stomach cancers. Conclusion: Type 2 diabetes is associated with a significantly increased risk of cancers of the liver, pancreas, colon, and rectum in postmenopausal women. The suggestion that diabetes severity further increases these cancer risks requires future studies.
Dietary fat in breast cancer survivalMakarem, N., Chandran, U., Bandera, E.V., & Parekh, N.
Journal titleAnnual Review of Nutrition
Laboratory evidence suggests a plausible role for dietary fat in breast cancer pathophysiology. We conducted a systematic literature review to assess the epidemiological evidence on the impact of total dietary fat and fat subtypes, measured pre- and/or postcancer diagnosis, in relation to breast cancer-specific and all-cause mortality among breast cancer survivors. Studies were included if they were in English, had a sample size ≥200, and presented the hazard ratio/rate ratio for recurrence, disease-specific mortality, or all-cause mortality (n = 18). Although the results are mixed, most studies suggested that higher saturated fat intake prediagnosis was associated with increased risk of breast cancer-specific and all-cause mortality. Postdiagnostic trans fat intake was associated with a 45% and 78% increased risk of all-cause mortality. Higher monounsaturated fat intake before and after diagnosis was generally associated with increased risk of all-cause and breast cancer-specific mortality, albeit the majority of the studies were statistically nonsignificant. Two studies evaluating omega-3 fat intake suggested an inverse association with all-cause mortality. Although there were too few studies on fat subtypes to draw definitive conclusions, high consumption of saturated fat may exert a detrimental effect on breast cancer-specific and all-cause mortality, whereas omega-3 fat may be beneficial. The inconsistent and limited evidence warrants research to assess the impact of consumption of fat subtypes on breast cancer recurrence and mortality.
Life course epidemiology in nutrition and chronic disease research: A timely discussionParekh, N., & Zizza, C.
Journal titleAdvances in Nutrition
Humans are exposed to a complex and changing combination of nutritional factors during the life course, necessitating their investigation over time to capture "critical periods of sensitivity." A life course approach provides a framework to examine trajectories and long-term effects of nutritional and other risk factors, particularly the role of timing, accumulation, and temporal relationships of these exposures in relation to chronic disease development. Currently, most epidemiologic research does not sufficiently address this issue in relation to disease etiology. Although applying a life course approach would augment our knowledge about disease development, this approach presents major challenges in designing, conducting, and analyzing studies. A scientific symposium was held that reviewed emerging research and discussed methodological concerns in applying the life course approach. The research presented at this session focused on the role of timing, with the pre- and postnatal and pubertal periods as critical windows of exposure for chronic conditions. Methodological issues and complexities in analyzing and selecting datasets were highlighted. This symposium elucidated unique study designs and statistical strategies to demonstrate the strengths of this methodology, and served as a catalyst for new research in the area of nutrition and chronic disease epidemiology.
Metabolic dysregulation of the insulin-glucose axis and risk of obesity-related cancers in the Framingham heart study-offspring cohort (1971-2008)Parekh, N., Lin, Y., Vadiveloo, M., Hayes, R.B., & Lu-Yao, G.L.
Journal titleCancer Epidemiology Biomarkers and Prevention
Background: Obesity-related dysregulation of the insulin-glucose axis is hypothesized in carcinogenesis. We studied impaired fasting glucose (IFG) and other markers of insulin-glucose metabolism in the Framingham Heart Study-Offspring Cohort, which uniquely tracks these markers and cancer>37 years. Methods: Participants were recruited between 1971 and 1975 and followed until 2008 (n = 4,615; mean age 66.8 years in 2008). Serum glucose, insulin, and hemoglobin A1c were determined from fasting blood in quartannual exams. Lifestyle and demographic information was self-reported. HRs and 95% confidence intervals (CI) of cancer risk were computed using time-dependent survival analysis (SASv9.3), while accounting for temporal changes for relevant variables. Results: We identified 787 obesity-related cancers, including 136 colorectal, 217 breast, and 219 prostate cancers. Absence versus presence of IFG 10 to 20 years and 20-years before the event or last follow-up was associated with 44% (95% CI, 1.15-1.79) and 57% (95% CI, 1.17-2.11) increased risk of obesity-related cancers, respectively. When time-dependent variables were used, after adjusting for age, sex, smoking, alcohol, and body mass index, IFG was associated with a 27% increased risk of obesity-related cancer (HR = 1.27; CI, 1.1- 1.5). Associations were stronger in smokers (HR=1.41; CI, 1.13-1.76). Increased risk was noted among persons with higher insulin (HR = 1.47; CI, 1.15-1.88) and hemoglobin A1c (HR = 1.54; CI, 1.13-2.10) for the highest (≤5.73%) versus lowest (≤5.25%) category. A>2-fold increase in colorectal cancer risk was observed for all blood biomarkers of insulin-glucose metabolism, particularly with earlier IFG exposure. Nonsignificant increased risk of breast and prostate cancer was observed for blood biomarkers. Conclusions: Earlier IFG exposure (>10 years before) increased obesity-related cancer risk, particularly for colorectal cancer. Impact: Our study explicitly recognizes the importance of prolonged IFG exposure in identifying links between glucose dysregulation and obesity-related cancers.
Sugary food and beverage consumption and epithelial ovarian cancer risk: A population-based case-control studyKing, M.G., Olson, S.H., Paddock, L., Chandran, U., Demissie, K., Lu, S.E., … Bandera, E.V.
Journal titleBMC Cancer
Background: Ovarian cancer is the deadliest gynecologic cancer in the US. The consumption of refined sugars has increased dramatically over the past few decades, accounting for almost 15% of total energy intake. Yet, there is limited evidence on how sugar consumption affects ovarian cancer risk.Methods: We evaluated ovarian cancer risk in relation to sugary foods and beverages, and total and added sugar intakes in a population-based case-control study. Cases were women with newly diagnosed epithelial ovarian cancer, older than 21 years, able to speak English or Spanish, and residents of six counties in New Jersey. Controls met same criteria as cases, but were ineligible if they had both ovaries removed. A total of 205 cases and 390 controls completed a phone interview, food frequency questionnaire, and self-recorded waist and hip measurements. Based on dietary data, we computed the number of servings of dessert foods, non-dessert foods, sugary drinks and total sugary foods and drinks for each participant. Total and added sugar intakes (grams/day) were also calculated. Multiple logistic regression models were used to estimate odds ratios and 95% confidence intervals for food and drink groups and total and added sugar intakes, while adjusting for major risk factors.Results: We did not find evidence of an association between consumption of sugary foods and beverages and risk, although there was a suggestion of increased risk associated with sugary drink intake (servings per 1,000 kcal; OR=1.63, 95% CI: 0.94-2.83).Conclusions: Overall, we found little indication that sugar intake played a major role on ovarian cancer development.